Peer-reviewed article

Impact of Pre-pregnancy BMI and Gestational Weight Gain on Fetomaternal Outcomes: A Cross-Sectional Analytical Study.

Chandrasekaran S, N U, Barathi A · 9 Mar 2026

Summary

Written by AI, not yet AICS's view · claude-haiku-4-5-20251001

This study examined how a mother's weight before pregnancy and weight gain during pregnancy affect outcomes for both mother and newborn baby. Researchers followed 300 pregnant women and found that mothers who were underweight, overweight, or obese had more complications like premature birth, caesarean sections, and delayed healing. Newborns born to these mothers had higher rates of low birth weight, large birth weight, and admission to intensive care units. The findings suggest that maintaining a healthy weight before pregnancy and appropriate weight gain during pregnancy can improve health outcomes for mothers and babies.

Key points

Obese mothers had caesarean section rates of 53.3% compared to other groups
Inadequate gestational weight gain was strongly associated with preterm delivery (73.5%) and low birth weight (71.4%)
Excess gestational weight gain was linked to post-term delivery (64.3%), induction of labour (69.6%), and caesarean section (46.4%)
Newborns of obese mothers had the highest macrosomia rates (36.7%) and NICU admissions (60%)
Delayed wound healing increased with maternal BMI, peaking in obese women (63.3%)

Limitations

The study does not specify which country or region it was conducted in, making it difficult to assess generalisability to different populations. The cross-sectional design cannot establish causation, only associations, and other unmeasured factors may influence the observed outcomes.

Abstract

Background Pre-pregnancy body mass index (BMI) and gestational weight gain (GWG) are modifiable determinants of adverse maternal and neonatal outcomes. This study evaluated the association of BMI and GWG, based on 2009 Institute of Medicine (IOM) recommendations, with fetomaternal outcomes in a tertiary care setting. Methods A prospective cohort study was conducted among 300 singleton pregnant women aged 20-34 years attending a tertiary hospital. Women were categorized by pre-pregnancy BMI (underweight n=90, normal n=120, overweight n=60, obese n=30) and GWG class (appropriate n=146, excess n=56, inadequate n=98). Maternal and neonatal outcomes were compared using chi-square/Fisher's exact tests. A p-value <0.05 was considered statistically significant. Results Obese women were predominantly ≥30 years (18; 60%) (p<0.001) and had higher lower-segment caesarean section (LSCS) rates (16; 53.3%) (p<0.001). Post-term delivery was common in overweight and obese groups (36; 60% and 18; 60%) (p<0.0001), while preterm delivery was higher in underweight women (35; 38.9%) (p<0.0001). Delayed wound healing increased with BMI, peaking in obese women (19; 63.3%) (p<0.0001). In GWG analysis, inadequate gain was strongly associated with preterm delivery (72; 73.5%) (p<0.001), whereas excess gain was linked to post-term delivery (36; 64.3%), induction (39; 69.6%), and LSCS (26; 46.4%) (p<0.001). Neonatally, macrosomia was highest in obese (11; 36.7%) and excess GWG (21; 37.5%) groups (p<0.001), while low birth weight was concentrated in inadequate GWG (70; 71.4%) (p<0.001). NICU admissions were highest in obese BMI (18; 60%) and inadequate GWG (68; 69.4%) (p<0.001). Conclusion Extremes of BMI and GWG are associated with adverse maternal and neonatal outcomes. Optimizing pre-pregnancy BMI and maintaining appropriate GWG may substantially improve fetomaternal outcomes.